1. Field of Invention
The present invention relates to the field of electronic circuits, and in particular to a comparator.
2. Description of Prior Art
Generally, a conventional comparator is used to compare two voltage signals and to output a comparative result.
A range of an offset voltage of the conventional comparator is very narrow, and the offset voltage is caused by changes in the external environment.
Theoretically, while a value of V+ is equal to a value of V−, an output of the conventional comparator will be reversed. However, in practical situations, the output of the conventional comparator will be reversed only while there is a tiny offset voltage between the value of V+ and the value of V−; the tiny offset voltage is caused by changes in the external environment and is impossible to be controlled.
It is not possible to use a conventional comparator when the application environment is in any of the following conditions (applying conditions):
While the value of V+ is equal to the value of V− plus a value of V1, then the output of the conventional comparator is permitted to be reversed.
V1 indicates the offset voltage. The value of V1 is constant.
Therefore, a new technical solution is needed in order to solve the problems mentioned above.